Chi Square Tests

Mala Mahadevan discusses how to perform a Chi Square test:

For any dataset to lend itself to the Chi Square test it has to fit the following conditions  –

1 Both  variables are categorical (in this case – exposure to smoking – yes/no, and health condition – sick/not sick are both categorical).
2 Researchers used a random sample to collect data.
3 Researchers had an adequate sample size.Generally the sample size should be at least 100.
4 The number of respondents in each cell should be at least 5.

This is an easy case for using R over T-SQL—the Chi Square test is built in, whereas you have to roll your own T-SQL code.  Mala does show you how to do this from within SQL Server R Services as well.

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